The technical literature very often refers to the international standard ISO 7730. That reference seems to have been accepted too quickly several years ago, without consulting the experts of the profession and without a real critical examination.Now we are facing a difficult situation because the profession recommends (and it is right) temperatures that are lower of several degrees to the ones advised by the standard. Furthermore, an important number of concrete researches demonstrate the very big uncertainties of the data the standard relies on. A serious warning is necessary.
A study on the effect of air temperature on productivity was carried out in telecommunications offices with an observational approach in call centre 1 and an intervention approach in the second call center by installing cooling units.The study shows that the productivity can be reduced by 5 to 7 % when the indoor temperatures increase.
A field survey was carried out to evaluate the thermal comfort perception of the occupants of a naturally ventilated public housing in Singapore to find out if that environment meets the Ashrae standard 55's 80 % criteria of acceptability.That survey also examined the adaptive behavior of the occupants in the use of windows, fans, and air-conditioning . Whether the thermal perception was influenced by different sessions of the day, building height and flat types was also part of the study.
The aim of that study was to develop a fuzzy controller for naturally ventilated buildings. This paper describes the process of designing a supervisory control to provide thermal comfort and adequate air distribution inside a single-sided naturally ventilated test room.
Thermal comfort variables were measured in Singapore mechanically ventilated classrooms. In parallel the cccupants filled questionnaires on their perception of the indoor climate. The results showed that ASHRAE Standard 55 was not applicable in free-running buildings in the tropics. The study showed that generally cool thermal sensations were more readily accepted by the classroom occupants than warm thermal sensations.
This paper presents the modeling of convective flows based on lattice Boltzmann methods in combination with a large eddy turbulence model. The used example is complex and three-dimensional.
Badly designed stables may affect the animals' health, but it is difficult to design a stable with acceptable ventilation rates and indoor comfort without the right tools or guidelines.For the design of animal housing facilities, the authors used the passive building simulation tool QUICK II, extended with a natural ventilation model, and an animal heat generation model.
This paper aims at comparing calculated and measured air flow distributions inside a naturally ventilated test room. Wind tunnel trials were carried out in the test room.Separate air flow and thermal modelling programs are used to predict the spatial distribution of the air flow and thermal comfort.
A new Adaptive Comfort Standard is included in the recently accepted revisions to Ashrae standard 55. That ACS permits warmer indoor temperatures for naturally ventilated buildings during summer and in warmer climate zones. It is based on the analysis of 21,000 sets of raw data compiled from field studies in 160 buildings located in different climatic zones on the 4 continents.
The current design standard BS EN ISO 7730 is based upon the work of Fanger dated 1995, dealing with a steady-state human heat balance model that leads to a prediction of the sensation of human thermal comfort for a given set of thermal conditions. That model was then developed for "conventional" environments. But is the current standard still applicable to more sophisticated environments such as offices with chilled ceiling, in combination with displacement ventilation ? This paper presents findings from a study that sought to answer that question.
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